<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
    function go({a=10,b=30}){
        console.log(a);
        console.log(b);
    }
    var obj={
        a:50,
        b:"quan"
    }
    // go(obj);
    go({});//10,30
    </script>
</body>
</html>